Gasoline insoluble lubricant



Patented Nov. 2a, 1944 John. D. Morgan, South Orange, and Russell E.Lowe, East Orange, N. J., assignors to Cities Service Oil Company, NewYork, N. Y., a corporation of Pennsylvania 7 7 No Drawing. ApplicationApril 17,

' Serial N0. 483,462

.5'Ciaims.-. (class-4 1). J a

v, and showed no corrosionin the copper strip test.

Our invention relates to an improved lubricant for valves or stopcocks;and more particularly to a plastic lubricant which is insoluble ingasoline motor fuels and other light hydrocarbons.

7 There is a considerable demand for such a lubricant particularly inthe valves of apparatus used in the handling of aromatic and other gasolines, especially in aeroplane equipment which operates over a ratherwide temperature range of from minus 50' F. to temperatures considerably above 100 F. Lubricants have been provided for plug cocks used inthe handling of naphtha and other hydrocarbons but as far as known theselubricants are greases containing varioussoaps as wellas graphite andmica. I

The primary object of the present invention is solid materials such asto provide a lubricant which can be used in the lubrication of themoving parts of apparatus for handling light hydrocarbons and which'ishighly resistant to the solvent action of such hYdl'Or' carbons.

A further object of the invention is to provide an adherent valvelubricant usable in contact with light hydrocarbons and which is free ofsoaps and solids such as talc, graphite or mica. 4

Another object of the invention is to. provide a lubricant which isinsoluble in aromatic gasovalves or moving parts of apparatus'used inthe handling of. gasolines and is effective over a considerabletemperature range including temperatures at which aircraft operate.Thefeatures of our invention are illustrated below in connection with aspecific example in which the proportions are y wei t.

Commercial stearamide, 4 parts, was melted with lO parts of commercialglycol-monophthal fate-monoalphaamino stearate and thoroughly mixed andworked to produce a homogeneous'solution. When this'mixture or solutionwas cooled to .room temperature it"had a consistency about like that ofa medium cup grease, that is an A. S. T. M. worked penetration of' 155to 200. It had a dropping point A. B. T. M. of 178.I".

' This lubricant passed the Navy test for low temperature ,greases whichis conducted with a ball bearing tester with a'torque of 3000 gm cm. TheNavy limit for a low temperature grease is seconds for one revolution onthis tester whereas the presentlubricant at minus 40 F. showed only 4seconds'and at minus" F. only 5 seconds.

The solubility of the lubricant in light hydrocarbons was tested with ahydrocarbon mixture consisting of 60 per-cent by volume of a commercialgasoline having an octane number of about 74, 5 percent of benzol, 20per cent of toluol, and 15 per cent of xylol. Itwas found that thelubricant was insoluble in this mixture at all temperatures up to aboutF., at which there was a very slight solubility. The solubility testwith this hydrocarbon mixture is regarded as more severe than would beencountered with any commerciai gasoline or other hydrocarbons, such asthe butanes, propanes, Diesel fuels and naphtha.

The effectiveness of the lubricant was tested by lubricating a springseated brass plug cock which was held in an electric oven at v F. untilequiperature of minus 50 F. The cock was found totum smoothly but wasvery stiff. At minus is an excellent lubricant for stopcocks and other"1 librium was attained. The operation of the plug cock was found to befree and easy. The same plug cock was lubricated and tested at a tem-40" F. the movement was. free and smooth.

The lubricant of the present invention is not a grease but may beregarded as a solid or plastic solution which is insoluble in gasolineand other light hydrocarbons over a wide temperature range includingtem'peratures higher than those normally encountered in the use-ofaircraft and other equipment in which motor fuels are han-' There may beinteraction between the NH: of the amine and the free -C 0OH of thedled.

glycol ester. The consistency of the lubricant may be varied somewhat bychanging the ratio of the steal-amide and the glycol-monophthalatemonoalphaamino stearate tosuit specific conditions or purposes. Injgeneralthe ratio of the 45 stearamide may vary from 3 to 5 parts, .to10 parts of the glycol ester, or from. approximately 1:2 to 1 :a. g'While thespeciflc constituents of the lubricant of the presentinvention provide an excellent motor fuel-insoluble lubricant it is tobe understood slightly .fewer carbon atoms may .be employed.

Likewise the glycol ester may vary somewhat from that named above byincluding an amino acid group of slightly more or fewer carbon atomsthan amino stearic acid. 'The amino group may be on a diflerent carbon.The phthalic acid group may likewise be changed so long as the generalcharacteristics of the mixture constituting the lubricant is notsubstantially altered.

The consistency of the lubricant may be. changed by varying theproportions oi! the two constituents so as to obtain an A. S. T. M.worked penetration of from 120 to 340. Such modifications, andlubricants containing equivalent materials are intended to be covered bythe appended claims.

Having described the invention in its preferred form what we claim asnew is: v

l. A lubricant which can be used in the lubrication of the moving partsof apparatus for handling light hydrocarbons and which is highlyresistant to the solvent action of such hydrocarbons consistingessentially of a mixture of from 3 to 5 parts by weight of stearamideand 10 parts by weight of a g stearate.

handling gasolines and other light hydrocarbons consisting essentiallyof a mixture of approximately 4 parts by weight of stearamide and 10parts by weight oi glycol-monophthalate-monoalphaamino-stea'rate.

4. A lubricant consisting essentially 0! from 3 to 5 parts by weight or.stearamide to approximately 10 parts by weight oi g1ycol-monophthal-.

ate-monoalphaamino. stearate.

5. A lubricant consisting essentially. of 4 parts by weight ofstearamide and 10 parts by weight. ofglycol-monophthalate-monoalphaamino stearate.

' JOHN D. MORGAN. RUSSELL E. LOWE.

